FIRST LECTURE. 93 



nachtrag %ur JVatuvges, der eingeweidewurmer, 

 etc. J)' 26. 



(192) Tyson, in Philos. Transactions , etc.; 

 Pallas, Dissert, cit. p. 13, no. 4. 



(193) Willis, Exercitationes de anima bruto- 

 rum^ J). 201, edit. gen. Redi, osservazioni intor- 

 110 agli animali viventi, etc. jt. 133. 



Those writers who have mantaiued that the hu- 

 man lumbrico'ides was exactly like the lumbricus 

 terrestris, have certainly been inattentive to the 

 species of the former, which are male and female, 

 while in the latter the worm is hermaphrodite. 



(191-) Zeder, Erster nachtrag., p. 2G, has sat- 

 isfactorily made it appear that all the signs detailed 

 by writers in order to settle the points of distinction 

 between the human lumbricus and that of horses 

 and hogs, are equivocal. 



(1Q5) Opere Jisico-inediche, tome i, p. 281. 



(196) Epistola cit. ad Jlndryiim, etc. 



(197) See pi. V, % i. 



(lyS) Versuch. JSTaturgeschichte, etc. p. 67. 



(199) Vermium intestinalium, etc. p.^Q; see 

 pi. V, fig. V. 



(200) See pi. Y, fig. i. One of these fibres is 

 longitudinal and dorsal, the other abdominal, and 

 the two others may be called lateral. 



Each fibre is composed of smaller filaments. 

 Vallisneri thought he discovered several dark 

 points in these, which he called spiral. 



Van-Phelsum has fully demonstrated the fal- 

 lacy of this observation. 



